Aham (1992)

Ramya visits her aunt who is a nun in a mental asylum. There she meets Sidharthan (Mohanlal) who leads a spiritual life in the mental asylum. She gets intrigued by his unique personality and starts studying him. Sidharthan on the other hand gets reminded of his x-wife (Urvasi) while interacting with Ramya closely and starts falling in love with her. But when he comes to know that he was just a subject to her study, things get murky.